Going Up: All About Shabbos Elevators

By: Rabbi Mordechai Frankel

Summer 2024

Historians claim that two hundred and twenty-four slaves were needed to operate the pulleys of the elevator system in the Colosseum of Rome. Thankfully, technology has come a long way since then. Modern elevators run on electricity which has necessitated the development of a Sabbath Mode. In Sabbath Mode, an elevator cab moves continuously up and down the elevator shaft, stopping at every floor. However, as will be explained, not all Sabbath Modes are the same.

Physics 101: How Elevators Work

There are two basic types of elevators in common use today: hydraulic and traction.

Hydraulic-Type Elevators

Hydraulics make use of the principle that liquid moved with low force over a large distance can be converted to movement with high force over a short distance. Take, for instance, a simple hydraulic jack (see Fig. 1). If the piston on the right has a surface area ten times that of the piston on […]

Warming Up: Do’s and Don’ts of Slow Cookers and Hot Plates on Shabbos

By: Rabbi Yaakov Heinemann

Summer 2024

Slow cookers and hot plates are the workhorses of many kosher kitchens as they enable the Sabbath-observant hostess to serve piping hot dishes to her family and guests to enhance the Shabbos seuda. In recognition of their importance in a Jewish home, it behooves us to review the halachos involving these appliances about which many users might not be aware.

This article will try to clarify the potential issues and how to address them in a practical way.

Slow Cookers

There are two basic types of electric slow cookers: an insert type (often referred to as a Crockpot®), in which a stoneware vessel sits inside a heated base; and a flatbed type, in which a metal pot sits atop a griddle base. Halachic issues involving their use include hatmana, shehiya and chazara. These will be explained below. (There are some more expensive models equipped with variable thermostats which make their usage on […]

Keeping Your Cool: Using a Refrigerator on Shabbos

By: Rabbi Chananya Jacobson

Summer 2024

As electricity began to be used as an energy source in the late 1800s and early 1900s, poskim considered how to view electricity from a halachic perspective. The posek hador, Rav Chaim Ozer Grodzinski zt”l, ruled that electric incandescent lighting is considered fire and, to reinforce this psak, he himself would recite Borei Meorei Haesh on an unfrosted incandescent light bulb. While this psak rapidly gained universal acceptance,[1] it only covered incandescent light bulbs, which are very similar to fire in that they generate both light and heat. What about the many other applications of electric power which do not share these characteristics?

Electricity and Halacha

There are two basic approaches to this issue. The Chazon Ish writes that activating any electric device is boneh (building), since the completion of a circuit involves attaching two parts and bringing the electrical device “to life.”[2]

Other poskim, especially Rav Shlomo […]